Gate arrangement

ABSTRACT

A GATE ARRANGEMENT IS DISCLOSED IN WHICH THE GATE IS OPENED BY THE WEIGHT OF A VEHICLE. SPRINGS URGE THE GATE TO THE CLOSED POSITION AND THE GATE IS HELD IN THE OPEN POSITION AGAINST THE ACTIONS OF THE SPRINGS BY A CATCH. TIMING MEANS FOR RELASING THE CATCH CONSISTS OF A TILT ARM ON EACH END OF WHICH IS LOCATED A TANK FOR A LIQUID. THE WEIGHT OF THE VEHICLE CAUSES THE ARM TO TILT TO RAISE ONE TANK ABOVE THE OTHER, CAUSING THE LIQUID TO FLOW FROM THE ONE TO THE OTHER. AFTER A TIME GOVERNED BY THE RATE OF FLOW OF THE LIQUID, THE WEIGHT OF THE LIQUID IN THE OTHER TANK IS SUFFICIENT TO ACTUATE THE CATCH.

Nov. 16, 1971 G. LOOTS 3,619,945

GATE ARRANGEMENT Filed Dec. 14, 1970 3 Sheets-Sheen 1 Nov. 16, 1971 G. LOOTS 3,619,945

GATE ARRANGEMENT Filed Dec. 14, 1970 3 Sheets-Shoot 2 Nov. 16, 1971 G. LOOTS GATE ARRANGEMENT 3 Sheets-Sheet 5 Filed Dec. 14, 1970 United States Patent 3,619,945 GATE ARRANGEMENT Gilliam Loots, 7 Windsor Drive, Durban N., Durban, Natal, Republic of South Africa Filed Dec. 14, 1970, Ser. No. 97,503 Int. Cl. Ef 15/20 US. CI. 4930 11 Claims ABSTRACT OF THE DISCLOSURE A gate arrangement is disclosed in which the gate is opened bv the weight of a vehicle. Springs urge the gate to the closed position and the gate is held in the open position against the actions of the springs by a catch. Timing means for releasing the catch consists of a tilt arm on each end of which is located a tank for a liquid. The weight of the vehicle causes the arm to tilt to raise one tank above the other, causing the liquid to flow from the one to the other. After a time governed by the rate of flow of the liquid, the weight of the liquid in the other tank is suflicient to actuate the catch.

This invention relates to gates which open and close automatically to allow a car or other vehicle to pass therethrough.

It is an object of the invention to provide a novel gate of this type. It is a particular object of the invention to provide a mechanism for the timing of the period during which the gates remain open which ensures a positive action while substantially obviating any variation in the period.

According to the invention, an automatic gate arrangement comprises means for opening the gate, timing means for determining the period during which the gate remains open, and means responsive to the timing means for closing the gate, the timing means comprising two recep tacles for a fluent material, means for moving one of the receptacles between a Ifirst position in which it is located at a higher level than the other receptacle and a second position in which it is located at a lower level than the other receptacle, duct means for conducting the fluent material from the one receptacle when it is in the first position to the other receptacle, and means responsive to the quantity of the material in the other receptacle for actuating the gate closing means.

Further according to the invention, the two receptacles are mountable at opposite ends of a tilt arm arranged to be tilted about a point between the two receptacles to move the one receptacle between the two positions.

In one form of the invention, the means for closing the gate comprises means arranged to urge the gate to the closed position.

According to a feature of the invention, the means for closing the gate further comprises catch means for holding the gate in the open position against the action of the urging means.

Another feature of the invention provides that the catch means is adapted to be released by means responsive to the weight of the material flowing into the other receptacle.

Yet another feature of the invention provides that the means for opening the gate comprises an actuating member adapted to be moved by a vehicle approaching the gate, and means to cause the gate to open when the actuating member is so closed.

According to a feature of this form of the invention, the actuating member comprises an arm adapted to be pushed over by the vehicle, and a line one end of which is connectable to the arm and the other end of which is connectable to means for opening the gate when the line is pulled by the arm.

3,619,945 Patented Nov. 16, 1971 'ice The tilt arm may be adapted to be tilted by means of a second line connectable to the line for opening the gate.

An embodiment of the invention is described with reference to the accompanying drawings, in which:

FIG. 1 is a view of a dual gate, showing the broad layout of the automatic openingand closing arrangement, one of the gates being omitted for the sake of clarity;

FIG. 2 is a sectional side view of a mechanism below ground level for timing the period during which the gate remains open; a mechanism for opening the gate is omitted from this view for the sake of clarity;

FIG. 3 is a fragmentary view of the view of FIG. 2, showing a bell-crank in a difference position;

FIG. 4 is a fragmentary sectional side view similar to that shown in FIG. 2, illustrating the mechanism for opening the gate and omitting the timing mechanism;

FIG. 5 is a view on arrows A--A in FIG. 4;

FIG. 6 is a detailed view of a catch for holding the gate in the closed position.

In the drawings, two gates 10 are mounted for pivotal movement about vertical axes on hinges 12 affixed to columns 14. The bottom of each gate is raised a small distance above the level of the ground to accommodate a bar 16 located directly below the gate.

This bar 16 is mounted for pivotal movement about a horizontal axis by means of brackets 18 on an inverted rolled steel channel 20 lying between the columns with the web 22 of the channel at ground level. At a distance equal to the track of the wheels of a motor car, two inverted U-formations 24 are formed in the bar 16. These formations normally project vertically upwardly and a flat 26 is welded in an upright position on each of them. In the centre of the bar 16 a rod 28 is mounted, also projecting vertically upwardly. The rod 20 is mounted on the bar 16 by means of a stirrup shaped bracket 30, this being done purely for rigidity. The rod must be long enough to enable the bumper of a vehicle passing through the gate to contact the rod and push it over. Mounted on the bar 16 in axial alignment with the rod 28 is an abutment bar 32 projecting vertically downwards through a hole 34 in the Web 22 of the channel 20. The function of this abutment bar is explained presently. A stop bar 36 is welded to the top of the bar 16 alongside each leg of the stirrup shaped bracket 30.

The stop bars form abutments for catches to be described presently for holding the gates in the closed position.

A drawbar 38 depends pivotally from the lower end of the abutment bar 32. Two wire ropes 40 and 42 are anchored to the lower end of this drawbar 38. The wire ropes pass between a pair of guide rollers 44 parallel to each other and parallel to the rod 16. These rollers 44 rotate about axles which are mounted on cross members 46 welded to plates 48 welded to and depending downwardly from the longitudinal centre of the flanges of the channel 20. The rollers 44 are closely spaced and prevent the ropes 40 and 42 from moving to the side of the channel.

After passing through the rollers 44 the rope 40 passes round a roller 50 carried on an axle mounted between the plates 48 and transverse to the rod 16. The rope 40 then passes upwardly and around another roller 52 parallel to the roller 50. The rope then passes along the channel 20 and is attached to a spigot 53 of a crank 54 mounted on an axle 55 carried in a bearing 56 in the web 22 of the channel 20, the crank being arranged to pivot about a vertical axis. The crank is urged by a tension spring 57 attached to the channel to a position in which the spigot 53 is on the outermost point of its path of movement as the crank pivots. The upper end of the axle 55 carries an arm 58 extending horizontally 3 under the gate and parallel thereto. The outer end of the arm 58 is provided with an upwardly extending U-shaped bracket 60 between the legs of which the bottom of the gate is received. Pivotment of the crank thus causes the gate to pivot, and vice versa.

Although not shown in the drawings, the rope 42 passes over a similar set of rollers and is attached to another crank below the other gate. A turnbuckle 62 is provided in each rope 40 and 42 to adjust the length thereof to enable the crank to be correctly positioned.

From the mechanism described so far, it can be seen that if the rod 28 is pushed over in either direction by a vehicle, this will cause the abutment bar 32 to move upwardly in a circular path. The ends of the ropes 40 and 42 will at the same time be drawn upwardly causing the other ends of the ropes to move towards the longitudinal centre of the channel 20 and thus to rotate the cranks. The gates will thus be opened.

It is necessary for the gates to be given an initial push in the direction in which it is desired that they should be opened. This is brought about by the positioning of the crank, and in particular of the spigots necessitated by the fact that it is necessary for the gates to open in both directions.

Furthermore, once the top of the rod 28 drops below the level of the bumper of the vehicle, it will no longer be moved downwards by the vehicle and the gates in this position are not yet fully open. The U-formations 24 and the flats 26 in the bar 16, are provided for this purpose. Once the gates have commenced opening, the vehicle advances through the gate and the tyres of the vehicles ride over the flats causing the rod 16 to rotate until the flats, and at the same time the rod 28, become horizontal.

It is necessary to provide apparatus to hold the gates in the open position against the action of the springs 57 until the vehicle has passed through the gates. To this end two bellcranks 70 are mounted one at each end of an axle 72 carried for pivotal movement about a horizontal axis between the plates 48, one crank being located adjacent each plate 48. Each bell crank 70 is urged to a position of equilibrium by a spring 76. The short arm 74 of each bellcrank projects obliquely upwardly into the path of the abutment bar 32. When the rod 28 is tilted to the substantially horizontal position, the abutment bar 32 comes into contact with the lower face of the short arm 74 and pushes the short arm aside until the abutment bar clears the upper end of the short arm.

Consequently, since the bellcrank 70 thereafter moves back into its position of equilibrium under the action of the spring 76, when the abutment bar begins to move downwardly again it comes into abutment with the upper end of the short arm 74 and is held in this position preventing the gates from closing when the vehicle moves off the flats 26. This situation is illustrated in FIG. 3 and by virtue of the provision of the two bellcranks 70, pertains in whatever direction the gates are opened.

It is necessary, once the vehicle has moved clear of the gate, to provide that the gates be closed. To this end a tilt arm 100 is mounted for pivotal movement on an axle 102 carried between the plates 48. At each end of the tilt arm a tank 104 for a liquid such as paraffin is carried. The tanks 104 are joined by a pipe 106. The tilt arm 100 pivots about the axle 102 between the positions shown in solid outline and in dotted outline respectively in FIG. 2. In the first mentioned position, which is the position occupied by the tilt arm when the gates are closed, the left hand tank is above the level of the right hand tank and thus the liquid in the left hand tank drains therefrom through the pipe 106 into the right hand tank. In the second mentioned position, shown in dotted outline, the right hand tank is above the level of the left tank and the liquid drains into the left hand tank.

A wire rope 108 is affixed to the left hand end of the titlt arm 100 and after passing around a guide roller 110 extends to the left (in the drawings) and is attached at 112 to the rope 40. Another wire rope 114 is attached to the right hand end of the tilt arm 100. It passes around a guide roller 116 and also extends to the left, being attached to the wire rope 42. When the gate is opened, the rope 40 is drawn to the right and the rope 42 is drawn to the left. The left hand end of the tilt arm consequently is dropped and the right hand end is raised so that the tilt arm moves into the dotted outline position.

A chain 118 connects the long arm of the bellcrank 70 to the left hand side of the tilt arm. When the gates are closed, the chain 118 is slack. However, as the gates are opened the left hand end of the tilt arm moves downwardly and the chain is arranged to be of such length that it becomes taught as shown in FIG. 4, just as the gate is full open. It is furthermore necessary for the rope 108 to be slack when the gate is fully open, allowing further downward movement of the left hand end of the tilt arm. For this reason care must be taken in selecting the point at which the rope 108 is connected to the tilt arm. Once the one gate is open, the right hand end of the tilt arm is raised above the left hand end and the liquid commences flowing from the right hand tank into the left hand tank. It should be understood that although the rope 114 prevents the right hand end of the tilt arm from tilting downwards, there is at this stage nothing except friction between the abutment arm 32 and the end of the crank 70, to prevent the left hand end from tilting downwards since the rope 108 is slack. There is however no tendency for the left hand end of the tilt arm to pivot downwards because, when the gates have just been opened, the weight of the liquid in the right hand tank prevents this. However, after a period of time determined by the density of the liquid and the rate of flow thereof through the pipe 106, sufficient liquid is transferred to the left hand tank for the moment thereof, acting through the bellcrank 70, to overcome the friction between the abutment bar 32 and the end of the short arm 74 of the bellcrank. The stop rail thus pivots to the left and the gate can now close. The springs 57 urging the gates to the closed position must be strong enough to overcome the weight of the liquid in the left hand tank when the gates close. The provision of the springs in the system may cause a certain amount of undesirable swinging of the gate about the closed position. A catch 120 suitable to prevent this is shown in FIG. 7.

The catch 120 comprises two bars 122 and 124, angularly located with respect to each other, and mounted by a stud 126 on each gate. Both bars 122 and 124 are pivotable on the stud 126, the movement with respect to the gate being limited by an abutment lug 127 between the bars welded to the gate. The bars are located with respect to each other by an abutment bar 128 welded to the bar 124 against which the bar 122 is urged by a tension spring 130. Swinging feet 132 and 134 are mounted at the lower ends of bars 122 and 124 respectively. These feet swing freely inwardly about t heir mountings 136 and 138 respectively, but their outward swing is limited by abutments in the form of lugs 140 and 142, welded to the lower ends of bars 122 and 124 respectively.

When the gate swings to the closed position, the outer edge of, for example, the swinging foot 134 meets the leading face of the stop bar 36 mounted on the bar 16. The swinging foot swings inwardly and upwardly and the stop bar 36 moves under it. Because of the momentum of the gate, the stop bar 36, when it contacts the inner edge of the other swinging fot 132 will force the bar 122 carrying that foot outwardly against the force of the spring This will allow the swinging foot 134 to clear the top of the stop bar 36 and it will drop into place behind the trailing face of the stop bar. The gate will not under normal circumstances be swinging so fast that it will push the bar 122 aside completely. It it does, the springs 57 are too strong.

What I claim is:

1. An automatic gate arrangement, comprising means for opening the gate, timing means for determining the period during which the gate remains open, and means responsive to the timing means for closing the gate, the timing means comprising two receptacles for a fluent material, means for moving one of the receptacles between a first position in which it is located at a higher level than the other receptacle and a second position in which it is located at a lower level than the other receptacle, duct means for conducting the fluent material from the one receptacle when it is in the first position to the other receptacle, and means responsive to the quantity of the material in the other receptacle for actuating the gate closing means.

2. A gate arrangement as set forth in claim 1, in which the two receptacles are mountable at opposite ends of a tilt arm arranged to be tilted about a point between the two receptacles to move the one receptacle between the two positions.

3. A gate arrangement as set forth in claim 1, in which the means for closing the gate comprises means arranged to urge the gate to the closed position.

4. A gate arrangement as set forth in claim 3, in which the means for closing the gate further comprises catch means for holding the gate in the open position against the action of the urging means.

5. A gate arrangement as set forth in claim 4, in which the catch means is adapted to be released by means responsive to the weight of the material flowing into the other receptacle.

6. A gate arrangement as set forth in claim 1, in which the means for opening the gate comprises an actuating member adapted to be moved by a vehicle approaching the gate, and means to cause the gate to open when the actuating member is so moved.

7. A gate arrangement as set forth in claim 6, in which the actuating member comprises an arm adapted to be pushed over by the vehicle, and a line one end of which is connectable to the arm and the other end of which is connectable to means for opening the gate when the line is pulled by the arm. I

8. A gate arrangement as set forth in claim 7, in which the tilt arm is adapted to be tilted by means of a second line connectable to the line for opening the gate.

9. The gate arrangement as set forth in claim 5 in which the catch means comprises a stop member movable into the path of the lever on the arm adapted to be tilted by the vehicle, the stop member being adapted to be withdrawn out of the path of the lever by a mechanism. responsive to a secondary movement of the tilt arm when the weight of the fluent material in the other receptacle exceeds a predetermined value.

10. An automatic gate arrangement according to claim 1, in which catch means is provided to hold the gate in the closed position, the catch means comprising a pair of spaced projections each adapted to pivot towards each other sufiiciently to allow an abutment to move into the space between them.

11. An automatic gate arrangement according to claim 10, in which the spaced projections are normally locatable in a position of equilibrium and are adapted to pivot away from each other against the action of spring means urging them to the position of equilibrium.

References Cited UNITED STATES PATENTS 521,993 6/1894 Savage et a1 4930 X 578,028 3/.1897 Von der Ropp 49--22 1,563,266 1 1/1925 Durham 49-21 X 2,538,470 1/1951 Peeples 49-30 X 2,624,569 I/ 1953 Peterson 49265 X 2,861,366 11/1958 Denison 49-269 3,081,937 3/1963 Kreider 49265 X 3,233,351 2/1966 Cook 49-132 X 3,497,996 3/ 1970 Stevens 4930 DENNIS L. TAYLOR, Primary Examiner US. Cl. X.R. 49263 

